Mafix Raises $5.4 Million to Commercialize Silicon Fertilizers that Remove CO2

Mafix’s fertilizer improves agronomic value for farmers and is developed through a drop-in process utilizing spare capacity on cement kilns

SEATTLE, Aug. 20, 2026 (GLOBE NEWSWIRE) -- Mafix, an industrial technology startup that turns abundant rocks into agronomically advantageous carbon-negative silicon fertilizers and other mineral products, today announced it raised $5.4M in pre-seed funding, led by Azolla Ventures with support from Counteract VC, Astera Institute, Plug and Play Ventures, Impact Science Ventures and a Dutch family office. With this funding, Mafix will commercially demonstrate its proprietary technology to produce 1,000 tons of its fertilizer that restores soil health, boosts crop yields and resilience, and reduces the need for traditional fertilizers. In the U.S., there is demand for silicon fertilizers, but producers cannot reliably obtain high-quality supply at relevant price. Mafix, with its permanent carbon sequestration fertilizer that has multiple value props for farmers, is meeting that demand.

Developed at Stanford University, Mafix’s mineral conversion process overcomes a key barrier to enhanced rock weathering, a strategy that seeks to use alkaline rocks to remove CO₂ from the atmosphere. Conventional enhanced rock weathering, which crushes and spreads common rocks like basalt, is limited by the extremely slow weathering rates of the mineral constituents. Mafix turns inert silicate rock into minerals that weather in as fast as a single growing season, so permanent carbon removal happens on the farmer's timeline. When applied to farmland, the fertilizer releases nutrients into the soil, improving yields, and removes CO₂ as stable bicarbonate.

“The alkalinity trapped inside silicate rocks is one of the largest untapped resources on the planet,” said Jade Marcus, CEO and cofounder of Mafix. “Our breakthrough is releasing it deliberately and quickly, transforming the most abundant rocks on Earth into a fertilizer that feeds crops and permanently removes CO₂ at the same time.”

Due to a decrease in global demand for carbon-intensive clinker, along with regional population trends and general seasonality, roughly 30% of today’s cement kiln capacity sits idle globally. By strategically partnering with cement producers to utilize spare capacity on kilns, Mafix’s drop-in process eliminates the need for expensive new facilities and opens access to existing logistical hubs to efficiently deliver product to customers, shortening supply chains and minimizing costs.

"Mafix's silicon fertilizer is designed to improve soil health and agricultural productivity while delivering a scalable solution for permanent CO₂ removal, addressing two critical global challenges with a single technology,” said Jillian Chase, Principal at Azolla Ventures. “Its use of existing cement infrastructure for manufacturing means it can scale quickly to address farmers’ immediate needs while Jade, Matt and the impressive Mafix team develop additional products via their mineral transformation technology.”

Beyond commercial demonstration, Mafix will use the funding to further advance its novel mineral conversion process for deployment across a broad range of feedstocks and unlock next-generation products, including new applications and markets beyond agriculture.

“Weathering rocks on land is one of the simplest ways to remove carbon from the atmosphere, but in our experience the payoff for landowners has often not been good enough,” said Andrew Shebbeare, Partner at Counteract VC. “With traditional minerals, slow weathering means payment delays and racking up measurement expenses for several years. Mafix minerals weather in a single growing season and offer real agronomic benefits to draw down carbon faster and make crops more resilient at the same time - a win-win for landowners and the climate.”

Mafix was founded by Jade Marcus, who was recently recognized as an Extraordinary California Women Founder and as a Forbes 30 under 30 List honoree, and Dr. Matthew Kanan, a professor of chemistry at Stanford University.

About Mafix
Mafix is a technology start-up leveraging one of the Earth’s largest untapped resources, found in silicate rocks, that improves crop resiliency and yields while permanently removing CO₂ from the atmosphere. Mafix is rethinking what the world's existing infrastructure can do by using spare capacity in cement kilns to transform idle industrial assets into engines for permanent carbon removal and food security. The company is now commercializing its first-generation climate-smart fertilizer and plans to extend its mineral conversion chemistry into new products, applications, and markets. Learn more: https://www.mafix.ag/

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Winter wheat trials conducted at LSU 2025

Mafix's wheat trials

Winter wheat trials conducted at LSU 2025

Mafix's wheat trials